Species number - body weight distributions are generally thought to be skewed to the right. While this pattern is well documented in vertebrates, comparative studies on species rich invertebrate taxa are still scarce. Here I show that the weight distributions of central European Coleoptera (based on 8257 species body weight data compiled from Freude et al., 1964-1994) are predominantly right skewed. Skewness and species richness per taxon were positively correlated. The number of modes of the body weight distributions was negatively correlated with species richness. 273 of the 558 genera had bimodal distributions. Species richness per genus did not significantly depend on mean genus body weight. In general the coleopteran size distributions differed from those of European Hymenoptera but were similar to the respective distributions of vertebrates. I conclude that we should be cautious when generalizing patterns found in one taxon.
Recent compilations of species richness for 54 European countries and large islands and linear spatial autocorrelation modelling were used to infer the influence of area and environmental variables on the number of species of clearwing moths (Sesiidae) in Europe. Area corrected species richness of rhizophagous Sesiidae peaked at about 40°N and decreased towards higher and lower latitudes. Most species rich was Greece (45 species), Bulgaria (37), Italy (35) and Romania (35). The area corrected species richness of xylophagous Sesiidae peaked at about 45°N with France (24) and Italy (22) being most species rich. Species richness was significantly positively correlated with area and the average yearly difference in temperature, and significantly negatively correlated with latitude. Island and mainland SAR slopes did not differ significantly, however island species richness per unit area appeared to be about 2 to 2.5 times lower than mainland species richness.
Although the sizes of the geographical ranges of plant and animal species are of major interest to macroecologists, the spatial distributions and environmental correlates of only a small group of animals and plants are well studied. Here data on the spatial distributions of 116 European clearwing moths (Sesiidae) was used to determine the patterns in spatial distribution, postglacial colonization and endemism. The spatial distributions of sesiids are significantly more coherent and there are fewer isolated occurrences and unexpected absences than predicted by a random sample null model. After correcting for environmental correlates, islands and mainland countries did not differ significantly in the number of species with small ranges. Polyphagous wood attending species were more widespread than those with other life histories. Species of Siberian origin had wider ranges than those of Mediterranean origin. Nestedness and species co-occurrence analysis did not support a unidirectional postglacial colonization from a Southern European refuge but colonization from both Southern and Eastern Europe. and Werner Ulrich, Marek Bąkowski, Zdeněk Laštůvka.